Oops

Hi, just prepping for the off. Put some water in for travelling as we're not going too far so not too concerned about weight. Filled hot water heater, Truma Ultrastore,switched it on. Again if we stopped we would have hot/warm water to wash hands. It has tripped the main RCD and keeps doing so. I have checked that there was water in there and there was . Everything else works. Any suggestions?

I think if it was a lack-of-water problem then it would be a thermal trip but as it's the RCD it's an electric problem. Could just be damp. If you're taking the van out anyway this will give it all a good airing. Else, run on gas for a few hours to dry things out a bit.

It's a case of knocking things off the list of possibles until you find the problem.